Friction draft rigging



G.y B. DOREY.

FRlcTloN DRAFT RIGGING.

APPLICATION FILED AUG`22, 1921.

W/TNESSES 2 SHEETS-SHEET I.

/N VE N TOR Patented Oct. 3, 1922.,

G. DoHEY.

FRICTION DRAFT HIGGINS.

` APPLICATION FILED AUG`22, 192I.

Patented Oct. 3, II922.

2 SHEETS-SHEET 2.

W/TNES SES GEORGE BINET DUREY, 0F MONTREAL, QUEBEC, CANADA. l

FRICTJION DRAFT RIGGING.

Application 'llecl August 22, 1921. Serial No. 494,192.

the like, and is especially related to that class lof draft riggings wherein wedging elements are used in connection 'with casings and friction members to create frictional resistance andaugment the cushioning power of the device. In gears of the identified type it is common practice to have wedging members re-act with great force transversely of the casing thereby tending tosplit this member. l

1t is therefore an object of the present invention to partially relieve the casing of this excessive strain by loosely mounting an auxiliary movable cage which will function as a wedge retaining member and take a portion of this transverse strain thereby permitting the main casing to more properly exercise its main function as a column member.

Another object of the present invention is to improve the construction of draft riggings whereby pressure transmitting members having a comparatively short travel and moving at a low velocity will displace friction resistance members a greater distance and at a greater velocity.

A main object ofthe invention is to provide novel means for'utilizin-g a definite pro-V portion of the energy used in compressing the draft gear as a means of increasing the resistant power of resistant members.

A `further object lof the invention is to provide a friction draft rigging which will be certain to release `"after compression. A difficulty hitherto experienced in gears of high capacity has been the liability-of the wedging elements binding against the casing walls and so preventlng the gear from returning to the normal release position.

Further my invention consists i'n certain novelties of design and construction of parts which will be more particularly pointed out in the annexed specification and claims. A

The abcoinpanying drawings illustrate an exampleief the physical embodiment of the invention as applied between the sills -of a railway car.

Figure 1. is a longitudinal horizontal sec# tional view through the complete gear as assembled, the parts being in the normal or. extended position.

-Figure 2. is a view similar to Figure 1.' showing the gear in the. fully compressed position. l l

Figure 3. is a sectional view taken through the gear on line 3--3.

Figure 4f. is a perspective view of the outer casing.

f Figure 5. is a perspective view of one of the friction shoes.

Figure. 6. is a perspective view of the inner frictional resistance member.

Figure 7. is a perspective view, of the inner casing or wedge retaining cage.

Figures 8 and 9 are perspective views f the wedge pressure'blocks known as pressure transmitting members.

ln the drawings 2 represents the drawbar of the coupler connected by means of key 3 to the yoke 4 in the Yusual rnembe'r, the yoke embracing the casing 5 and the -whole being located between the center sills 6 and 7. ln the illustrations the casing is formed to abut against front stops 10 and 11 which are secured to the center sills, rearstops 8 and 9- also secured to the centery sills constitute draft gear abutments under bufiing strains.

rlhe outer casing 5 is preferably formed of rectangular shape with one end closed and the Vother end open and is formed with-two oppositely beveled faces 12 on the walls at some distance from the open end of the casing. 'llhe upper portion of these walls are preferably made straight as at 5a and constitute guides between which the wedge retaining cage 13 moves and is thereby secured rom undue sidewise movement. The

outside walls 13a -of the cagel are also naad-e straight to slide between the walls 5a of the casing 5. The inner walls of the cage 18 are beveled in opposite directions as at la and 15. Top and bottom walls 13b securely tie the two portions of the wedge retaining cage. The beveled'portions of the cage at 14 are opposed to those at 12 of the casing 5 and interposed between these members are wedge friction shoes 16 which have beveled surfaces 17and 1 8 formed to register with the corresponding beveled surfaces .on the cage 13v and on the casing 5. Theinner walls of theshoes as at 19 are then parallel and `beof the friction shoes 16 are forced when the inner cage and outer casing are moved to- "wards each other.

The central frictionl member 20 has its front surface formed in the shape of a wedge by means of front walls 22 which are angularly disposed relatively to each other. This surface 22 together with surface 15 of the cage 13 form a wedge shaped recess on each side of the center of the draft rigging within which the wedge block pressure transmitting members 23 and 24 operate. rlhe wedge block pressure transmitting members 23 and 24 are disposed on each side of the longitudinal center of the draft rigging and are each formed with bearing surface 23a and 24a constituting one face of a wedge which register with surfaces 15 of the cage 13. The adjacent surfaces of these' pressure transmitting members as at 23b and 24b register with surfaces 22 of the central friction member 20. On the draft rigging being compressed the pressure transmitting members 23and 24 are forced into the outer casing and by reason of their bearing on the inclined walls of the cage they are also caused to move transversely towards each other.'

interposed between the-wedge block pressure transmitting members 23 and. 24 and the rear stops is a follower plate 25. As the wedge blocks move transversely of the draft rigging the faces 23c and 24c of these members co-acting with face 25a of the follower 25 friction is created at these points.

In order to stabilize the pressure trans mitting members and prevent one from moving faster than the other these members have been formed' with overlapping portions; for this purpose'wedge block 23 has j been fitted with a recess 23d into which projection 24d of wedge block 24 is adapted to move.

Friction member 20 is hollowed out to receive outer spring 26 and inner spring 27 which are adapted to return the gear to normal release position after compression and to maintain all the parts in operative relation.

The operation of the draft place as ,follows ln draft or bumng strains the draft gear is compressed by the approach of follower 25 to casing 5, the rear follower abutting against 'rear stops 8 and 9.' This movement causes wedge block pressure transmitting members 23`and 24 to be moved longitudinally into the casing 5 and owing to their gear takes bearingon the inclined surfaces 15 of they wedge cage 13 there will also be transverse movement along face 25a of the follower 25 thus creating considerable friction at these points. The inward longitudinal and inward transverse movement of the pressure transmitting members is strongly resisted by the central friction member 22 which has its upper sur-face formed in the form of an apex. Bygeason of the inclination of the upper walls of member 22 this member is` forced a greater distance than the wedge pressure transmitting members inasmuch `as the latter moving towards each other in a transverse direction create a squeezing action on the inclined walls of the former. During this action the outward force incidental to the transverse movement ofthe wedge blocks 23 and 24 is resolved into an inwardly acting force through theA medium of the wedge cage, which having inclined Walls 15 converts this outward reactionvinto a longitudinal thrust, which acting on surface 17 of the wedge shoes 16 through the medium of inclined wall 14 of the wedge cage again converts this force into a transverse one ending topress the friction shoes 16 against the friction member 22. In this manner the direction of the forces is reversed and a portion of the energy generated by the impact of the instrumentalities which it is desired to `cushion will be utilized to increase the effectiveness of the resistant portion of the rigging. rlhe ends of the shoes 16 as at 18, on'the ends remote from the wedge cage, are also inclined and co-act with similarly inclined surfaces 12 of tlhe casing 5 thereby providing a very stable mechanism inasmuch as the shoes are forced against the friction member from both ends.

The wedge pressure transmitting members are adapted to move with the follower in the same ratio as the coupler but displacing the friction member 22 a greater distance and at a greater velocity the advantage of great resistance with relatively small bearing pressures is secured thereby obviating the disadvantage of seizure between the friction members. As the friction vmember 22 is moved inwardly into the casing the outer spring 26 and inner spring 27 are compressed thereby.

@n release of the mechanism the springs expand returning the friction member 22 in a forward directionwhich has the effect of moving the pressure transmitting members in an outward direction both transversely and "'.longitudinally and at the same time moving the follower and coupler back to the normal release position.

rllhe liability of the draft rigging binding and failing to release is entirely eliminated in this invention inasmuch as the entire fric tion mechanism as comprised by the fol-V lpressure transmitting members having a acarrear tion shoes are only related to the casing through the medium of the flaring eveled walls as at 12'and in the event of these members being tightly wedged the entire mechanism comprised of the above parts will be moved bodil forward out of engagement 4with the casing. Such movement, however small, immediately breaks all the wedging engagement and the parts immediately resume their l normal release position, the springs furnishing the necessary energy to return the gear to the release position and at the same time maintain all Athe parts in operative relation.

While l have shown and described with particularity only a single embodiment of my to the exact structural details thus illustrated and described; butcintendv to cover all forms and arrangementsiwhich come within the -terms employed in the, definitions of my invention constituting the appended claims.

What l claim is:

1. In a friction draft rigging, pressure transmitting members having adjacent inclined surfaces, one of such surfaces being adapted to act upon and displace a friction member and the other of such surfacesbeing adapted to move friction shoes against the friction member.

2. In a frictiondraft rigging, the coml bination with adrawbar having movement,

pressure transmitting members having adjacent inclined surfaces, one of such surfaces bein adapted to act upon and displace a frictlon 'member a greater distance than the drawbar moves andthe other of such surfaces being adapted to force friction shoes against the friction member.

3. ln a friction draft rigging, a follower,

surface movable along the face of such follower and two surfaces angularly disposed thereto, one of such surfaces being adapted to act upon and displace a friction member and the other of such surfaces being adapted to move friction shoes ,against the friction member.

4. ln a friction draft rigging for railway cars, a friction member mounted for reci rocatory motion between parallel faces of lriction shoes, relatively approachable members having wedging engagement with the outer faces of the friction shoes, wedge pressure transmitting members having adjacent surfaces, one of which is adapted to displace the friction member and the other of such surfacesb'eing adapted to force the relatively approachable members together.

5. A friction draft rigging for railway cars comprising a friction member mounted for reciprocatory motion between parallel faces of friction shoes, the said shoes having their ends wedge shaped and oppositely inclined; wedging means acting on each end invention l do not desire to be limited vtion shoes which have oppositely inclined wedge shaped ends and wedging means act-` ing on each end of such shoes for forcing them against the friction member.

7 -In a friction draft rigging the combination with a casing of frictionshoes in wedging engagement therewith and a friction member in sliding engagement with the shoes and wedge ressure transmitting members adapted to force the shoes against the friction member and move the latter relatively to the shoes. y

8. ln a friction draft rigging the combi nation with a central friction member of casings having oppositely inclined walls, one of such casings being contained within the other -and constituting a wedge retaining cage, wedge friction shoes interposed be: tween the inclined walls of the casings and ing adjacent faces, one -face being in wedging engagement witlfmthe inner casing and the other face in wedging engagement -with the central friction member and'springs -for yieldingly lmaintaining all the parts in operative relation. v v

10. lln a draft rigging in combination an outer casing,'an inner'casing, shoes interposed therebetween and adapted to be forced inwardly axially to the line of draft on relative .approach of the casing, a longitudinally movable central friction element re'- sisting such movement and being movable relatively to the shoes and springs for yieldingly maintaining the parts in operative relation. e

11. ln a friction draft rigging 'in combination a drawbar, a casing, a central fric-v tion'member and friction shoes in engagementftherewith, wedges adapted to move the 95 l the central frictionjrnember and wedge@ terposed between thel wedges and the shoes for the purpose of forcing the latter axially to the line of draft against t-he friction member.

l2. In a friction draft rigging for railway cars the combination with a casing of pressure transmitting members adapted to 'displace a friction member, a cage supporting the pressure transmitting members, and wedge shoes co-operating with the cage and tlievcasing for retarding the pressure transmitting-members through the medium of the friction member and springs for yield,- ingly maintaining the parts in operative relation.

13. In! a friction draft rigging for rail-` way cars the combination with a casing of pressure transmitting members having a transverse reaction of a loosely mounted wedge retaining`cage adapted to take the transverse thrust ;y the walls of the said casing constituting guides for the wedge cage.

14. In a friction draft rigging for railway cars wedge pressure transmitting members having longitudinal and transverse movement and wedging means co-operating bers consisting of wedges each having a. i

innercasings of a friction mechanism come prising inner and outer members, the outer members having their outer faces inclined and registering with similarly tapered faces* on the walls of the casings, and the inner walls of such outer members being straight and disposed in the line of draft; the said outer members being adapted to be forced against the inner member on relative appreach of the casings, and pressure transmitting members adapted to move the inner portion of the friction mechanism relatively to the outer portion and springs for yieldingly maintaining the parts 1n operative relation.

In testimony whereof I have hereunto set my hand in the presence of two witnesses.

GEORGEBINET DoREY.

Witnesses:

.JAMES B. SMITH,

R. J. LESLIE. 

